Take a good look at where/how you usually tie up, like that, and build a rig hook that accommodates your needs. There's no wrong way to build it if it's safe and does what it's supposed to do. First one I ever saw (didn't call it a rig hook, back then) was on a lake here close to home...it was an old framing square with a hole in one end...anchor rope was attached to the hole, the square was slipped through the expansion joint between two bridge sections on top of a piling. The old man who made it was fishing out of a 14' jon boat, so it wasn't like it had to hold a lot of weight. Seemed to be working like a champ everytime I saw him up there using it!